Because microorganisms lie on the skin, standard invasive medical procedures require a patient's skin, where the procedure is to take place, to be disinfected prior to the procedure. This skin preparation is important in order to minimize the risk of infection to the patient.
Alcohol has long been recognized as a fast acting broad-spectrum disinfectant. Alcohol-based prep solutions have many advantages over soap- or water-based prep solutions, such as reduced prepping and solution drying time. However, alcohol is flammable and its use and application on a patient should be carefully controlled in order to minimize the fire hazard created when such an alcohol-based prep solution is used. Indeed, in its January 1992 Guidance on Surgical Fires, the ECRI, (formerly the Emergency Care Research Institute) stated that approximately ten surgical patient fires come to its attention per year. These fires may ignite on or in the patient and may cause considerable injury to the patient. Today's surgical rooms, patient care facilities and procedures may utilize an increasing number of electrical equipment and devices. When this equipment and/or these devices are used in the vicinity of flammable solutions or vapors, the health care practitioner must be particularly careful to avoid such accidents. If alcohol-based solution is dispensed from an applicator having no flow control mechanism, in certain circumstances, the solution can flow excessively fast and “pool” up on the body, thereby increasing the potential hazard.
Additionally, subsequent to prepping, a patient is often covered with a surgical cloth drape. This drape may collect flammable vapors as any excess alcohol dries and vaporizes. This remaining alcohol vapor and/or liquid can then ignite with the addition of a significant heat source, such as electrosurgical or electrocautery units. Other ignition sources may include defibrillators, heated probes, drills and burs, argon beam coagulators, fiber optic light sources and cables and lasers used with the free-beam (bare-fiber) method. Often, this environment is made more combustible by the common use of oxygen in the surgical area, creating an oxygen rich atmosphere.
Many different antimicrobial applicators exist but could be improved. First generation applicators, as depicted in, for example, U.S. Pat. No. 4,183,684, allow the applicator contents to flow in large uncontrolled amounts. Other antimicrobial applicators that accommodate an ampoule that is broken for activation exist but could also be improved. One such type of applicator includes a lever mechanism on a side of the applicator wherein the lever mechanism is partially located within the applicator. When the lever mechanism is depressed, the internal portion of the lever applies pressure on the ampoule to break the ampoule and release the solution contained therein. Examples of applicators with external side lever mechanisms include U.S. Pat. No. 5,302,358 issued to Anderson et al. on Apr. 12, 1994; U.S. Pat. No. 5,425,915 issued to Phillips et al. on Jun. 9, 1995; and U.S. Pat. No. 6,371,675 issued to Hoang et al. on Apr. 16, 2002 each incorporated herein by reference. Other applicators provide a flexible portion of the applicator body at the location of the ampoule to break the ampoule and release the contents contained therein such as those disclosed in U.S. Pat. No. 4,893,730 issued to Bolduc on Jan. 16, 1990, U.S. Pat. No. 5,098,297 issued to Chari et al. on Mar. 24, 1992; and U.S. Pat. No. 5,791,801, each incorporated herein by reference.
These types of applicators are problematic because they may allow excessive amounts of the antimicrobial solution to flow onto the patient where it could pool and create a significant fire hazard if the antimicrobial solution is flammable. This is due in large part because both designs rely on gravity and the free flow of solution from the applicator to the foam application pads to dispense the applicator contents. As a consequence, if the applicator is not positioned to prevent solution flow, unwanted residual solution will continue to flow. In addition, even when the applicator is positioned to prevent solution flow, the free communication between the solution storage and the foam applicator allows fumes to continue to escape into the operating environment. Furthermore, a patient is often covered by a surgical cloth drape after prepping, i.e., the disinfecting procedure, takes place. When dispensation of the solution is not sufficiently controlled, a significant amount of the antimicrobial solution may collect on the surgical drape. Again, if the antimicrobial solution is flammable, a potential exists for an injury to the patient and the healthcare professionals in the area. Also, this inability to adequately control the flow of antimicrobial solution on and around the patient increases the likelihood that the solution will stain material in the area.
For user and patient safety, therefore, solution flow control is an extremely important characteristic of a skin prep applicator. A means to control flow is especially important for a skin prep applicator dispensing a flammable solution, such as an alcohol-based antimicrobial solution. The importance of flow control increases as the amount of dispensable solution increases.
More recently, applicators have been developed to control solution flow by customizing the applicator pads with slits of various numbers, such as in co-owned U.S. Pat. No. 6,371,675, which is incorporated herein by reference.